1. Field of the Invention
This invention relates to text display on a digital computer system, and in particular to the highlighting of information in a hypertext system.
2. Description of Related Art
A hypertext system, as that term is used in this specification, is a system for the display of text information grouped as documents. Within documents there are references, called links, to other documents or portions of the same document. Text associated with a link may be highlighted or displayed in a way that indicates that there is a link. When a link is selected, the document indicated by the link is displayed, either replacing the document containing the selected link or in another window. A link is generally selected by pointing at the text associated with the link (using a mouse, trackball, cursor keys, tab keys, or similar pointing means) and indicating the selection by a key or button press.
For example, in the court decision In re Alappat (Federal Circuit, 1994), there are a number of references to Diamond v. Diehr (Supreme Court, 1981). In a hypertext system whose documents are court decisions, the Alappat decision would contain links to the Diehr decision at the places where it is referenced. The reference to Diehr would be highlighted and when the reference is selected, the Diehr decision would be displayed.
Hypertext systems are well-known in the art. For a tutorial on hypertext systems, see “Hypertext: An Introduction and Survey” by Jeff Conklin (Computer, September 1987, pages 17-41). More references are described in Hypertext/Hypermedia: an annotated bibliography, compiled by Michael Knew and Steven D. Atkinson (ISBN: 0-313-27221-2, Greenwood Press, 1990). Many prior art hypertext systems also contain features beyond the definition of a hypertext system given above, such as the links to graphical or audio information as well as other documents.
The documents in a hypertext system may be stored on a mass storage device, such as a magnetic disk or CD-ROM, locally-attached to the computer system on which the documents are being displayed. The documents can also be stored on one or more networked document servers, where selection of a link results in a request being sent over the data communications network from the computer system on which the documents are being displayed to the networked document server holding the desired document, and that document being returned over the network for display. An example of the latter document storage method is the World Wide Web, a hypertext system where documents are stored on servers throughout the world.